caddy-frontend/test: Workaround requests issue with Accept-Encoding

requests set Accept-Encoding header, but in the testr environment we
want to have full control over its behaviour, thus not setting any header if
not really wanted.

As there is not known way to avoid setting the header (skip_accept_encoding is
internal to httplib) set dummy Accept-Encoding header, which is enough for our
environment.

software/caddy-frontend/test/test.py

@@ -571,6 +571,9 @@ class SlaveHttpFrontendTestCase(HttpFrontendTestCase):
     if headers is None:
       headers = {}
     headers.setdefault('REMOTE_USER', 'SOME_REMOTE_USER')
+    # workaround request problem of setting Accept-Encoding
+    # https://github.com/requests/requests/issues/2234
+    headers.setdefault('Accept-Encoding', 'dummy')
     session = requests.Session()
     session.mount(
       'https://%s:%s' % (domain, port),
@@ -593,6 +596,9 @@ class SlaveHttpFrontendTestCase(HttpFrontendTestCase):
     if headers is None:
       headers = {}
     headers.setdefault('REMOTE_USER', 'SOME_REMOTE_USER')
+    # workaround request problem of setting Accept-Encoding
+    # https://github.com/requests/requests/issues/2234
+    headers.setdefault('Accept-Encoding', 'dummy')
     headers['Host'] = domain
     return requests.get(
       'http://%s:%s/%s' % (real_ip, port, path),
@@ -1165,10 +1171,7 @@ http://apachecustomhttpsaccepted.example.com:%%(http_port)s {
       raise ValueError('JSON decode problem in:\n%s' % (result.text,))
     self.assertFalse('remote_user' in j['Incoming Headers'].keys())
 
-    self.assertEqual(
-      'gzip',
-      result.headers['Content-Encoding']
-    )
+    self.assertFalse('Content-Encoding' in result.headers)
 
     self.assertEqual(
       'secured=value;secure, nonsecured=value',
@@ -1186,10 +1189,7 @@ http://apachecustomhttpsaccepted.example.com:%%(http_port)s {
       raise ValueError('JSON decode problem in:\n%s' % (result.text,))
     self.assertFalse('remote_user' in j['Incoming Headers'].keys())
 
-    self.assertEqual(
-      'gzip',
-      result_http.headers['Content-Encoding']
-    )
+    self.assertFalse('Content-Encoding' in result_http.headers)
 
     self.assertEqual(
       'secured=value;secure, nonsecured=value',
@@ -2019,10 +2019,7 @@ http://apachecustomhttpsaccepted.example.com:%%(http_port)s {
       raise ValueError('JSON decode problem in:\n%s' % (result.text,))
     self.assertFalse('remote_user' in j['Incoming Headers'].keys())
 
-    self.assertEqual(
-      'gzip',
-      result.headers['Content-Encoding']
-    )
+    self.assertFalse('Content-Encoding' in result.headers)
 
     self.assertEqual(
       'secured=value;secure, nonsecured=value',
@@ -2039,10 +2036,7 @@ http://apachecustomhttpsaccepted.example.com:%%(http_port)s {
       raise ValueError('JSON decode problem in:\n%s' % (result.text,))
     self.assertFalse('remote_user' in j['Incoming Headers'].keys())
 
-    self.assertEqual(
-      'gzip',
-      result_http.headers['Content-Encoding']
-    )
+    self.assertFalse('Content-Encoding' in result.headers)
 
     self.assertEqual(
       'secured=value;secure, nonsecured=value',
@@ -2164,9 +2158,10 @@ http://apachecustomhttpsaccepted.example.com:%%(http_port)s {
     headers.pop('Keep-Alive', None)
 
     self.assertEqual(
-      {'Content-type': 'application/json',
-       'Set-Cookie': 'secured=value;secure, nonsecured=value',
-       'Content-Encoding': 'gzip', 'Vary': 'Accept-Encoding'},
+      {
+        'Content-type': 'application/json',
+        'Set-Cookie': 'secured=value;secure, nonsecured=value',
+      },
       headers
     )
 
@@ -2182,10 +2177,7 @@ http://apachecustomhttpsaccepted.example.com:%%(http_port)s {
       raise ValueError('JSON decode problem in:\n%s' % (result_direct.text,))
     self.assertFalse('remote_user' in j['Incoming Headers'].keys())
 
-    self.assertEqual(
-      'gzip',
-      result_direct.headers['Content-Encoding']
-    )
+    self.assertFalse('Content-Encoding' in result_direct.headers)
 
     self.assertEqual(
       'secured=value;secure, nonsecured=value',
@@ -2206,10 +2198,8 @@ http://apachecustomhttpsaccepted.example.com:%%(http_port)s {
         result_direct_https_backend.text,))
     self.assertFalse('remote_user' in j['Incoming Headers'].keys())
 
-    self.assertEqual(
-      'gzip',
-      result_direct_https_backend.headers['Content-Encoding']
-    )
+    self.assertFalse(
+      'Content-Encoding' in result_direct_https_backend.headers)
 
     self.assertEqual(
       'secured=value;secure, nonsecured=value',
@@ -2532,9 +2522,10 @@ http://apachecustomhttpsaccepted.example.com:%%(http_port)s {
     headers.pop('Keep-Alive', None)
 
     self.assertEqual(
-      {'Content-type': 'application/json',
-       'Set-Cookie': 'secured=value;secure, nonsecured=value',
-       'Content-Encoding': 'gzip', 'Vary': 'Accept-Encoding'},
+      {
+        'Content-type': 'application/json',
+        'Set-Cookie': 'secured=value;secure, nonsecured=value'
+       },
       headers
     )
 
@@ -2550,10 +2541,7 @@ http://apachecustomhttpsaccepted.example.com:%%(http_port)s {
       raise ValueError('JSON decode problem in:\n%s' % (result_direct.text,))
     self.assertFalse('remote_user' in j['Incoming Headers'].keys())
 
-    self.assertEqual(
-      'gzip',
-      result_direct.headers['Content-Encoding']
-    )
+    self.assertFalse('Content-Encoding' in result_direct.headers)
 
     self.assertEqual(
       'secured=value;secure, nonsecured=value',
@@ -2574,10 +2562,7 @@ http://apachecustomhttpsaccepted.example.com:%%(http_port)s {
         result_direct_https_backend.text,))
     self.assertFalse('remote_user' in j['Incoming Headers'].keys())
 
-    self.assertEqual(
-      'gzip',
-      result_direct_https_backend.headers['Content-Encoding']
-    )
+    self.assertFalse('Content-Encoding' in result_direct_https_backend.headers)
 
     self.assertEqual(
       'secured=value;secure, nonsecured=value',
@@ -2625,9 +2610,10 @@ http://apachecustomhttpsaccepted.example.com:%%(http_port)s {
     headers.pop('Keep-Alive', None)
 
     self.assertEqual(
-      {'Content-type': 'application/json',
-       'Set-Cookie': 'secured=value;secure, nonsecured=value',
-       'Content-Encoding': 'gzip', 'Vary': 'Accept-Encoding'},
+      {
+        'Content-type': 'application/json',
+        'Set-Cookie': 'secured=value;secure, nonsecured=value'
+      },
       headers
     )
 
@@ -2676,9 +2662,10 @@ http://apachecustomhttpsaccepted.example.com:%%(http_port)s {
     headers.pop('Keep-Alive', None)
 
     self.assertEqual(
-      {'Content-type': 'application/json',
-       'Set-Cookie': 'secured=value;secure, nonsecured=value',
-       'Content-Encoding': 'gzip', 'Vary': 'Accept-Encoding'},
+      {
+        'Content-type': 'application/json',
+        'Set-Cookie': 'secured=value;secure, nonsecured=value',
+      },
       headers
     )
 
@@ -2720,10 +2707,8 @@ http://apachecustomhttpsaccepted.example.com:%%(http_port)s {
 
     self.assertEqual(
       {
-        'Vary': 'Accept-Encoding',
         'Content-Type': 'application/json',
         'Set-Cookie': 'secured=value;secure, nonsecured=value',
-        'Content-Encoding': 'gzip',
       },
       headers
     )
@@ -2769,10 +2754,8 @@ http://apachecustomhttpsaccepted.example.com:%%(http_port)s {
 
     self.assertEqual(
       {
-        'Vary': 'Accept-Encoding',
         'Content-type': 'application/json',
         'Set-Cookie': 'secured=value;secure, nonsecured=value',
-        'Content-Encoding': 'gzip',
       },
       headers
     )